Department of Medicine, Universidade da Região de Joinville (UNIVILLE), Joinville, Brazil.
Department of Immunology, Institute of Biomedical Sciences, University of São Paulo (ICB-USP), São Paulo, Brazil.
Adv Exp Med Biol. 2021;1321:21-31. doi: 10.1007/978-3-030-59261-5_2.
The recently emerged coronavirus named severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causal agent of COVID-19, is the newest threat to human health. It has already infected more than 54.5 million people worldwide, currently leading to more than 1.3 million deaths. Although it causes a mild flu-like disease in most patients, lethality may increase to more than 20% in elderly subjects, especially in those with comorbidities, like hypertension, diabetes, or lung and cardiac disease, and the mechanisms are still elusive. Common symptoms at the onset of illness are fever, cough, myalgia or fatigue, headache, and diarrhea or constipation. Interestingly, respiratory viruses have also placed themselves as relevant agents for central nervous system (CNS) pathologies. Conversely, SARS-CoV-2 has already been detected in the cerebrospinal fluid. Here, we discuss several clinical features related to CNS infection during COVID-19. Patients may progress from headaches and migraines to encephalitis, stroke, and seizures with leptomeningitis. However, the pathway used by the virus to reach the brain is still unknown. It may infect the olfactory bulb by retrograde neuronal transportation from olfactory epithelium, or it could be transported by the blood. Either way, neurological complications of COVID-19 add greatly to the complex pathophysiology of the disease. Neurological signs and symptoms must alert physicians not only to worst outcomes but also to future possible degenerative diseases.
最近出现的冠状病毒被命名为严重急性呼吸综合征冠状病毒 2（SARS-CoV-2），是 COVID-19 的病原体，是对人类健康的最新威胁。它已经在全球范围内感染了超过 5450 万人，目前导致超过 130 万人死亡。尽管它在大多数患者中引起轻度流感样疾病，但在老年患者中，死亡率可能会增加到 20%以上，尤其是在患有合并症（如高血压、糖尿病、肺部和心脏疾病）的患者中，其机制仍难以捉摸。疾病发作时的常见症状有发热、咳嗽、肌肉疼痛或疲劳、头痛和腹泻或便秘。有趣的是，呼吸道病毒也已成为中枢神经系统（CNS）疾病的相关致病因子。相反，SARS-CoV-2 已在脑脊液中被检测到。在这里，我们讨论 COVID-19 期间与 CNS 感染相关的几种临床特征。患者可能从头痛和偏头痛进展为脑炎、中风和伴有脑膜脑炎的癫痫发作。然而，病毒到达大脑的途径仍不清楚。它可能通过嗅球从嗅上皮逆行神经元运输而感染嗅球，也可能通过血液运输。无论哪种方式，COVID-19 的神经系统并发症极大地增加了疾病的复杂病理生理学。神经系统体征和症状不仅应引起医生对最坏结果的警惕，还应引起对未来可能发生的退行性疾病的警惕。
